When talking in proper circles, especially to non-techies, and in non-theatre settings (such as high school, church, etc.), it acceptable to simply say 'bamber', a faux contraction of 'Bastard Amber'. It saves a lot of explaination and odd looks.

One minor problem with bastard amber gels is that they seem to 'wear out' (become faded, brittle) as fast as, say, blue. This could either be due to the opacity, or simply because they are used so often -- it is in the perfect visual range for the human eye in that it's very close to the hue of reflected sunlight.